function f() {
  var a = this.g
  let data = []
  for (let i = 0; i < a.length; i++) {
    let arr = []
    for (let k = 0; k < a[i].cityList.length; k++) {
      let ikname= a[i].cityList[k].name
      let arr1 = []
      for (let m = 0; m < a[i].cityList[k].areaList.length; m++) {
        let ikmname= a[i].cityList[k].areaList[m].name
        arr1.push(
          {
            value: ikmname,
            label: ikmname,
          }
        )
      }
      arr.push(
        {
          value: ikname,
          label: ikname,
          children:arr1
        }
      )
    }
    data.push({
      value: a[i].name,
      label: a[i].name,
      children:arr
    })
  }
}